The present invention generally relates to the medical field, and more specifically, but not exclusively, relates to the sampling of bodily fluids.
The acquisition and testing of body fluids is useful for many purposes, and continues to be of importance for use in medical diagnosis and treatment, and in other diverse applications. In the medical field, it is desirable for lay operators to perform tests routinely, quickly and accurately outside of a laboratory setting, with rapid results and a read-out of the resulting test information. Testing can be performed on various body fluids, and for certain applications, it is particularly related to testing of blood and/or interstitial fluid. Such fluids can be tested for a variety of characteristics of the fluid or analytes contained in the fluid, in order to identify medical conditions, determine therapeutic responses, assess progress of treatments and the like.
A common medical test is the measurement of blood glucose levels. The glucose level can be determined directly by analysis of the blood, or indirectly by analysis of other fluids, such as interstitial fluid. Diabetics are generally instructed to measure their glucose levels several times a day, depending on the nature and severity of their diabetes. Based upon observed patterns in the measurement of glucose levels, the patient and physician can determine the appropriate level of insulin to be administered, also taking into account such issues as diet, exercise and other factors.
In testing for the presence of analytes such as glucose in a body fluid, test systems are commonly used which take advantage of oxidation/reduction reaction, which occurs using an oxidase/peroxidase detection chemistry. The testing reagent is exposed to a sample of the body fluid for a suitable period of time, and there is a color change if analyte (glucose) is present. Typically, the intensity of the change is proportional to the concentration of analyte in the sample. The color of the reagent is then compared to a known standard, which enables one to determine the amount of analyte present in the sample. This determination can be made, for example, by visual check or by an instrument, such as a spectrophotometer at a selected wave length, or a blood glucose meter. Electrochemical and other systems are also well known for testing body fluids for properties of constituents. Typically, a fingertip or some other body location of a patient is lanced with a lancet in order to obtain a body fluid sample.
Although fingertips generally provide an ample supply of blood, repeated lancing of fingertips can be quite painful due to the high concentration of nerve endings in the fingertips. Therefore, there has been a trend towards sampling fluids from alternate sites on the body, where the nerve concentrations are lower, such as the forearm. As should be appreciated, since alternate sites have lower nerve concentrations, the patient experiences less pain when lancing the alternate site. However, these alternate sites usually produce less fluid as compared to fingertips. Consequently, it has been a goal to reduce the amount of fluid needed for a successful test. To achieve this goal, it is desirable to ensure that as much fluid as possible is transported from the incision to the test area so as to minimize waste.
Thus, there remains a need for improvement in this field.